I am trying to access a single endpoint device through the MAX BR1 Mini - I have a static IP and would like to allow the endpoint to communicate through three separate ports.
I know that I should not have these “open” for security concerns, but that is how it needs to be. the endpoint is not initiating communications.

is there any setup information available from anyone who has done this?

3. Repeat for each port, or change the port selection to a range if they are sequential.
4. Click save and apply.

Of note here is the Cellular 1 WAN IP in the screenshot. Its a private IP allocated to sim by the mobile network operator who provides carrier grade NAT to my device, so these port forwarding rules won’t work. This is how most network operators do it unless you pay extra for a public IP - which is a bad idea for all the reasons you might think.